Description

Short description of error
Imported custom split normals are not used for mirrored parts using mirror modifier.

Exact steps for others to reproduce the error

Import geometry via fbx/obj with custom split normals.

Add mirror modifier.

BTW having custom split normals after all in blender is totally awesome if you had to work with cad converted geometry (ProE/Solidworks and so on). Thank you for integrating this to blender - you guys are awesome!